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Labyrinths, or maze caves represent zones of extreme porosity in karst. They are, in addition to large voids (rooms), presumed precursors to breccia zones in paleokarst as seen in many petroleum reservoirs. At the same time, speleogenesis of labyrinth structures is enigmatic as most common caves are either linear or dendritic. We have studied several variants of labyrinths in formerly glaciated stripe karsts in Scandinavia. The stripe geometry limits the mazes to basically 2 dimensions, which makes them favourable for analysis and modelling experiments. Using geometric and palaeocurrent analysis from detailed mapping, we have investigated speleogenetic processes by ice-contact on a model of discrete fracture network which integrates the effects of dissolution kinetics. In contact with dynamic ice as an insoluble barrier, labyrinth geometries very similar to our field cases can develop both under influent and effluent conditions. Subglacial waters will inherently suffer long and intimate contact with freshly crushed rock flour prior to entry in the karst. Modelling the effects of partially or near-saturated entry waters show that near-saturated waters develop more complex networks which compare more closely to our field cases than those produced from highly undersaturated waters.
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